Examining the role of attention focus walking training on conscious motor processing during rehabilitation by older adults at risk of falling: A randomized controlled trial

This study examined the impact of walking training with different attention focus instructions on real-time conscious motor processing and fall-related rehabilitation outcomes in older adults at risk of falling. A total of 102 community-dwelling older adults (mean age = 75.2 years, SD = 6.8 years) were randomly assigned to three groups: no attention focus walking group (NAFWG), external attention focus walking group (EAFWG), or internal attention focus walking group (IAFWG). All groups underwent 12 training sessions. Assessments were conducted at baseline, post-training, and six months later, measuring real-time conscious motor processing, functional balance and gait, balance ability, functional mobility, walking ability, trait conscious motor processing propensity, fear of falling, and recurrent falls. The EAFWG showed significant reduction on real-time conscious motor processing immediately after training (p = 0.015). No changes were observed for the IAFWG and NAFWG. All groups showed significant improvements in functional balance and gait (p < 0.001) and balance ability (p < 0.001) post-training. Implementing external focus instructions during walking training could be a feasible and beneficial strategy for reducing real-time conscious motor processing, which may improve walking performance and prevent falls in older adults. Further research is needed to examine the sustained benefits of these interventions and determine optimal training dosage for older adults with different risks of falling in fall prevention.

Do attentional focus instructions affect real-time reinvestment during level-ground walking in older adults?

This study represents the first attempt in exploring whether attentional focus instructions could affect real-time reinvestment (conscious movement processing) in older adults during level-ground walking. Forty-five community-dwelling older adults were instructed to walk at a self-selected pace along a 6-m level-ground walkway under three randomized attentional focus conditions (i.e., Internal, External, and Control) for a total of fifteen trials (five trials for each condition). Electroencephalography (EEG) T3-Fz coherence was utilized as an objective measurement of real-time reinvestment during walking. The Chinese version of the Movement-Specific Reinvestment Scale (MSRS-C) was used to measure the trait reinvestment propensity. Results revealed that the EEG T3-Fz coherence did not differ among the three conditions. The EEG T3-Fz coherence at the Control condition was not correlated with the scores of the MSRS-C. Our findings suggest that the measurement of trait reinvestment propensity (MSRS-C) may not be sensitive enough to reflect real-time reinvestment. Moreover, attentional focus instructions do not affect real-time reinvestment during level-ground walking, possibly due to the low level of motor task difficulty in level-ground walking for healthy older adults. Future studies should investigate this influential issue with a more challenging walking task.

Real-time conscious postural control is not affected when balancing on compliant surface by young adults

Previous research has illustrated that real-time conscious postural control (i.e., reinvestment - shifting from movement automaticity to a more consciously controlled and monitoring of movement) increased with standing task difficulties among healthy older adults. However, such association has not been investigated in the younger population. This study attempted to examine real-time conscious postural control among healthy young adults when performing different standing tasks on a compliant (foam) surface. T3-Fz EEG (electroencephalography) coherence, indicative of real-time conscious postural control, was recorded during the standing tasks (i.e., wide base on foam (WBF), narrow base on foam (NBF) and tandem stance on foam (TAF)). Body sway was also recorded by a motion capture system. Participants' perceived difficulty on the different standing tasks was evaluated by the Visual Analogue Scale (VAS). Results revealed that while body sway and perceived difficulty increased significantly with task difficulties, T3-Fz EEG coherence did not differ among standing tasks. In addition, no differences of any measures were found between young adults with high and low trait reinvestment propensity. Our findings indicate that young adults do not pose higher real-time conscious postural control when task difficulty increases. We also add support to the existing literature; the between-group effect of trait reinvestment appears to be minimal in real-time.

The role of reinvestment in conservative gait in older adults

Previous research suggests that reinvestment (i.e. conscious control of movements) is associated with inefficient information processing and compromised movement strategies in older adults during walking. We examined whether reinvestment propensity is associated with conservative gait behaviour in older adults. Trait Reinvestment propensity was measured using the Movement Specific Reinvestment Scale (Chinese version) (MSRS-C). Thirty-eight older adults were categorized into 'Low Reinvestor Group' (LRG) (MSRS-C < 27) and another 38 were categorized into 'High Reinvestor Group' (HRG) (MSRS-C > 38). There were no significant differences in physical and cognitive abilities between groups. Participants were asked to walk along a 6-m straight level-ground walkway at a self-selected pace under conditions of no instruction (Baseline), instruction related to self-focus on body movements (BI), and instruction related to the external environment (EI). No significant difference was found in gait behaviour between LRG and HRG at Baseline. However, significant changes, indicative of conservative gait patterns, were found in LRG when given instructions that prompted them to consciously control their body movements. No changes were observed in HRG under external-related instructions that are assumed to reduce conscious motor processing and improve motor performance. Our findings contradict previous views on the association between trait reinvestment propensity and compromised motor performance in older adults, which potentially reduces justification for reducing trait reinvestment propensity in older adults. We also suggest that MSRS is insensitive to reflect the degree of conscious control during gait tasks. Our findings also implicate the potential detrimental effect of applying inward-focus-related instructions in healthcare rehabilitation settings.

Conscious Postural Control During Standing on Compliant Surface by Older Adults

This study examined the real-time objective measurement of conscious postural control ("reinvestment") in older adults when standing on a compliant surface using electroencephalogram (EEG) coherence. Twenty-nine older adults participated in the study and their Alpha2 T3-Fz and Alpha2 T4-Fz EEG coherence during standing at three different positions on foam including wide-base standing on foam (WBF), narrow-base standing on foam (NBF) and tandem standing on foam (TAF) were measured. Participants were also required to respond to a Visual Analog Scale (VAS) to determine their perceived task difficulty after each standing position. Three 2 × 3 (Groups[low reinvestor, high reinvestor] × Standing positions[WBF, NBF, TAF]) analysis of variance (ANOVA) with repeated measures were conducted to determine differences between high and low reinvestors in three standing positions (WBF, NBF, TAF) at the primary outcome measures. The main effects of standing positions at VAS and Alpah2 T3-Fz EEG coherence were discovered but without interaction. The results suggested that when standing task difficulty increased, older adults generally elevated their real-time conscious postural control together with perceived task difficulty. It implicates that Alpha2 T3-Fz EEG coherence can be considered as a real-time objective conscious postural control measurement during balance assessment and rehabilitation if further large-scale studies could find its discriminative power between high and low reinvestors.